1. Field of the Invention
The present invention is related to ski boots, having a shell base to which an upper is attached, and a rear spoiler journalled on the shell base, that can be latched, in the skiing position, on the sides of the boot, which is connected to the front portion of the upper.
2. Discussion of Background and Material Information
Known ski boots of this type have the advantage of clearing a very large rear portion of the upper, and this facilitates introduction and removal of the foot of the skier. Another advantage lies in the fact that the latching of the rear spoiler on the sides of the boot in the skiing position guarantees a firm and stable rear support. Generally, these boots can be classified in two different categories.
In the first category, as has been disclosed in Italian Patent No. 1,087,581 for example, the upper is capable of pivoting frontwardly by the flexion of the front spoiler, journalled at the end of the boot, in the zone corresponding to the flexion fold of the foot, and by the rotation of the rear spoiler about a journal axis on the shell base which is located, either in the zone corresponding to the heel, or the zone corresponding to the malleolis. Also, as is clear from the description of the boot, the pivot amplitude of the rear spoiler is limited in the area of its latching system on the sides of the latter by the span of at least one nesting slot that cooperates with a projecting element. In such a boot, it appears that it is the flexible quality of the front spoiler alone, in the zone corresponding to the flexion fold, that determines the value of the forces that resist frontward flexion of the upper. Moreover, since the spoiler does not comprise means capable of modifying these flexibility qualities, the value of the resisting forces is fixed immutably, i.e., it cannot be adjusted in accordance with the skill-level of the skier, his weight, his strength, etc.
In the second category, such as has been described in the French Patent Application No. 2,640,123, the upper of the boot includes a front spoiler which is borne by a sleeve journalled on the shell base in the zone of the malleolis and of a rear spoiler journalled on the lower and rear extensions originating from said sleeve in the heel zone. This embodiment differs from the one described previously, in that it is the assembly of the upper, the sleeve as well as the front and rear spoilers, that pivots about a single rotational axis constituted by the journal of the sleeve on the shell base. Moreover, this journal being located in the zone of the malleolis, the upper thus pivots in its entirety about an axis that corresponds substantially to the axis of the ankle. Insofar as controlling the flexion forces is concerned, i.e., the value of the forces resisting the frontward pivoting of the upper, this embodiment of the boot provides for the implementation of control means of a known type, arranged either between the sleeve and the shell base, or between the rear spoiler and the shell base, instead of using the flexibility of the front spoiler as in the Italian Patent No. 1,087,581. It is thus possible to adjust the value of the forces resisting the pivoting of the upper.
As we have just noted in the ski boots described hereinabove, the rear spoiler fulfills a variety of functions: it closes the rear portion of the boot, participates in the retention of the lower part of the leg of the skier when it is connected to the front spoiler in the closure position of the upper, constitutes the main front-to-rear support element because it latches on the sides of the boot, and accompanies the pivoting of the upper in the rear-to-front direction during frontward flexions by the skier. However, the function of controlling the flexion forces is still done, either by the front spoiler, or by specific means interacting between the shell base and a portion of the upper such as the sleeve or the rear spoiler. Such an arrangement in fact localizes all the forces on a single part of the boot, as a matter of fact, on a relatively reduced area of the latter, and necessitates the use of rigid and resistant materials for the manufacture of special provisions on the concerned boot area.